There is an authentication system that compares and crosschecks biological information registered in an authentication apparatus with biological information read from an authentication apparatus and manages entries and leaving of people in and from a room when a person tries to enter or leave in or from the room. For the authentication, the user inputs a biological information item and an ID number assigned to the user. Then, the authentication system extracts registered biological information associated with the input ID number and compares the extracted single biological information with the input single biological information so as to execute the authentication.
Japanese Laid-open Patent Publication Nos. 2001-140519, 2004-5532, and 2008-40763 are examples of related art.